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| author | Namhyung Kim <namhyung@kernel.org> | 2020-10-07 11:13:11 +0300 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-10-07 15:57:58 +0300 |
| commit | bef69bd7cfc363ab94b84ea29102f3e913ed3c6c (patch) | |
| tree | 3d6238ec052d7bbcad56138b6760c33c109116e7 /tools/lib/perf | |
| parent | 6fcd5ddc3b1467b3586972ef785d0d926ae4cdf4 (diff) | |
| download | linux-bef69bd7cfc363ab94b84ea29102f3e913ed3c6c.tar.xz | |
perf stat: Fix out of bounds CPU map access when handling armv8_pmu events
It was reported that 'perf stat' crashed when using with armv8_pmu (CPU)
events with the task mode. As 'perf stat' uses an empty cpu map for
task mode but armv8_pmu has its own cpu mask, it has confused which map
it should use when accessing file descriptors and this causes segfaults:
(gdb) bt
#0 0x0000000000603fc8 in perf_evsel__close_fd_cpu (evsel=<optimized out>,
cpu=<optimized out>) at evsel.c:122
#1 perf_evsel__close_cpu (evsel=evsel@entry=0x716e950, cpu=7) at evsel.c:156
#2 0x00000000004d4718 in evlist__close (evlist=0x70a7cb0) at util/evlist.c:1242
#3 0x0000000000453404 in __run_perf_stat (argc=3, argc@entry=1, argv=0x30,
argv@entry=0xfffffaea2f90, run_idx=119, run_idx@entry=1701998435)
at builtin-stat.c:929
#4 0x0000000000455058 in run_perf_stat (run_idx=1701998435, argv=0xfffffaea2f90,
argc=1) at builtin-stat.c:947
#5 cmd_stat (argc=1, argv=0xfffffaea2f90) at builtin-stat.c:2357
#6 0x00000000004bb888 in run_builtin (p=p@entry=0x9764b8 <commands+288>,
argc=argc@entry=4, argv=argv@entry=0xfffffaea2f90) at perf.c:312
#7 0x00000000004bbb54 in handle_internal_command (argc=argc@entry=4,
argv=argv@entry=0xfffffaea2f90) at perf.c:364
#8 0x0000000000435378 in run_argv (argcp=<synthetic pointer>,
argv=<synthetic pointer>) at perf.c:408
#9 main (argc=4, argv=0xfffffaea2f90) at perf.c:538
To fix this, I simply used the given cpu map unless the evsel actually
is not a system-wide event (like uncore events).
Fixes: 7736627b865d ("perf stat: Use affinity for closing file descriptors")
Reported-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Barry Song <song.bao.hua@hisilicon.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201007081311.1831003-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib/perf')
| -rw-r--r-- | tools/lib/perf/evlist.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c index 2208444ecb44..cfcdbd7be066 100644 --- a/tools/lib/perf/evlist.c +++ b/tools/lib/perf/evlist.c @@ -45,6 +45,9 @@ static void __perf_evlist__propagate_maps(struct perf_evlist *evlist, if (!evsel->own_cpus || evlist->has_user_cpus) { perf_cpu_map__put(evsel->cpus); evsel->cpus = perf_cpu_map__get(evlist->cpus); + } else if (!evsel->system_wide && perf_cpu_map__empty(evlist->cpus)) { + perf_cpu_map__put(evsel->cpus); + evsel->cpus = perf_cpu_map__get(evlist->cpus); } else if (evsel->cpus != evsel->own_cpus) { perf_cpu_map__put(evsel->cpus); evsel->cpus = perf_cpu_map__get(evsel->own_cpus); |